The Duke of Cambridge has confessed he was worried when the Prince of Wales was diagnosed with Covid-19 and says the family are doing “everything we can” to protect the Queen and Duke of Edinburgh.

William’s admissions were made in an interview with his wife where they also joked about the challenges of home schooling their children and the “ups and downs” of living in lockdown.

And the couple revealed like the rest of the country they are staying in touch with members of their family via video calls.

The duke also praised veteran fundraiser Captain Tom Moore who has raised millions for the NHS walking lengths of his garden describing him as an “absolute legend”.

Talking about his father, who suffered from mild symptoms of Covid-19 and recovered after a period of self-isolation, William told the BBC: “I have to admit at first I was quite concerned, he fits the profile of somebody, at the age he’s at, which is, you know, fairly risky, and so I was a little bit worried.

“But my father has had many chest infections, colds and things like that over the years and so I thought to myself (if) anybody’s going to be able to beat this it’s going to be him.”

The duke said he was reassured by doctors and friends who advised him by the time Charles reported his symptoms he was “probably past the worst of it”, and his mind was put at rest after speaking to his father but at his age of 71 “you do worry a bit more”.

William said that as a “mad walker” his father found it hard remaining inside during his seven-day isolation period: “He loves his walking. So I think he found it quite difficult, especially also, I think, with his mental health, being stuck inside and not being able to go for walks.”

The Queen, 93, has been staying at Windsor Castle, with the Duke of Edinburgh, 98, as a precaution for a number of weeks and the duke said he also has concerns for his grandparents.

Princes George (right), Louis (centre) and Princess Charlotte joining in a national applause for the NHS (Kensington Palace/Twitter/PA)

Kate added: “That’s so true, and actually your father and my parents and our families and things like that have really loved keeping in touch with the children, because it’s really hard at times, particularly over family times like Easter not seeing each other.

“It gets a bit hectic, I am not going to lie, with a two-year-old.”

The duke quipped: “For some reason he sees the red button and he always wants to press the red button.”

William also praised fundraiser Capt Moore.

The duke described the 99-year-old as an “absolute legend” and has written to him and made an undisclosed donation to his appeal.

The royal added: “It’s incredible, I did see it on the news the other night and I thought good on him.

“It’s amazing and what I love also is that he’s a 99-year-old war vet who’s been around a long time, knows everything and it’s wonderful that everyone kind of has been inspired by his story and his determination.”